Oven appliances generally include a cabinet that defines a cooking chamber for receipt of food items for cooking. Heating elements are positioned within the cooking chamber to provide heat to food items located therein. The heating elements can include a bake heating element positioned at a bottom of the cooking chamber and/or a broil heating element positioned at a top of the cooking chamber. The heating elements can be gas burners that burn a combustible gas within the cooking chamber in order to provide heat to food items located therein.
In oven appliances with gas burners, a flame spreader is generally mounted above the gas burners in order to facilitate uniform heat distribution within the cooking chamber. In particular, the flame spreader can increase in temperature during operation of the oven appliance and provide a significant source of radiative heat to food items within the cooking chamber. Heated gases generated by the gas burners can provide the heat needed to increase the temperature of the flame spreader. However, a boundary layer of relatively cool air positioned adjacent the flame spreader can hinder convective heat transfer between the gas burner's heated gases and the flame spreader.
The thickness of the boundary layer and the velocity and temperature profiles of the boundary layer can affect convective heat transfer between the gas burner's heated gases and the flame spreader. In general, a relatively thinner boundary layer and a relatively high speed boundary layer can facilitate increased convective heat transfer. Also, facilitating direct contact between the gas burner's heated gases and the flame spreader can improve heat transfer therebetween.
Accordingly, a flame spreader with features for decreasing a thickness of a boundary layer positioned adjacent the flame spreader would be useful. In addition, a flame spreader with features for increasing a velocity or a temperature or both of a boundary layer positioned adjacent the flame spreader would be useful.